Nobody really seems to know how long domestic dollar installs will last all the guarantees seems to be based around them still being ~90% after 20-25 years but even after that it doesn’t mean you have to replace them they will still seemingly carry on generating power for ever just at an ever decreasing rate. Assuming the decay is roughly linear you are talking 80% after 50 years which is still going to be a decent amount of power. The real question is in 20-30 years will the tech have improved enough that we want to upgrade?
Solar panels
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Soldato
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Its a good point but many variables to consider. I watched a program where they went into things like some single panels cant handle a partial cloud blocking its array so it generated way less than expected. Then there is how dirty the panels get and how often you should clean them to ensure high efficiency. I do think they get better materials and the tech helps over time but I also think a decent panel will last long enough that unless you can source new ones to replace them which are ridiculously undercutting the original panels value, 80% after 25 years of use is not bad and likely not worth ditching them at all.
80% is looking more like 40+
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I've just had 12*380w panels installed with a Solis inverter for just over £4.5k. For me it's not really about making that investment back but more about saving money. I used the Scottish governments interest free loan to pay for it rather than using my own savings. I did look at a battery install at the same time but it more than doubled the cost and given I've only recently bought an EV, I wasn't sure what my usage was going to be so just opted for solar for now. Might re-visit battery storage in the future.
@Journey have you done a full write up of your system and how you designed it on the forum?
I feel like this is something we’ll within my capability (and then finding an installer) but to be honest, I don’t really know where to find the resources to get started.
I feel like this is something we’ll within my capability (and then finding an installer) but to be honest, I don’t really know where to find the resources to get started.
Nope, not done a write up. I designed it by accident (sort of), after I got fed up of all the installers taking the pee with the prices for the kit I wanted, and I only found out what I wanted by doing lots of research and asking lots of questions to various solar installers, electricians, watching some videos etc. It was planned for a long while, and adding the battery was the icing on the cake with the lower prices, and the ability to use Octopus Agile Export, and a different import tariff, which means I make money every day back on it, but that was secondary to having a whole house UPS. Obviously having a BEV is also great with solar, as I can charge it when I am not using the excess, or when the export prices are low, and I am due to have a heat pump installed in 2022, so that will be a another bonus.
We are due to remortgage next year and considering taking some more equity out to ha be solar installed.
Are there any good websites to look at in order to work back estimated costs, savings and energy production?
On a note of batteries, I'm on Octopus Go...can I have a battery installed without solar in order to power the house using the cheaper energy over night?
Are there any good websites to look at in order to work back estimated costs, savings and energy production?
On a note of batteries, I'm on Octopus Go...can I have a battery installed without solar in order to power the house using the cheaper energy over night?
You don’t need solar to make use of a battery. During the winter I generate very little solar so I fill the battery up overnight using off peak electricity which is about 14p per kw cheaper than peak daytime cost.
I'm wondering if this is the way forward for me instead of the cost of the solar.
Can you have the batteries installed in a loft space?
Probably but the loft is likely to get very toasty so you may need to check wether the battery can operate in those conditions.
Mine has a fan and it spins up all the time especially when under load and that’s just in a porch area which isn’t particularly hot.
A large amount of the installers who ran quotes for me asked if I wanted loft install or elsewhere, my concerns were that it would get hot, but having seen a battery in operation in the peak of summer it seems they do get warm, but some of the packs are designed to operate most efficiently at 30-50 degrees C, allowing the best charge-discharge range, and best efficeincy, most packs now will use LiFePO4 chemistry cells.
I considered just getting a battery, but solar is so cheap now it didn't make sense to get one without the other, and i want to be totally gas free by this time next year as well, so really preferred that option. Do you have a budget in mind?
Where in Scotland are you? I live in Fife and I didn’t think it was worthwhile installing solar panels as it would take so long to pay back the initial cost.
Soldato
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Kirkcaldy. I did it more to save on my reliance on the grid and I'm not too fussed about ROI. It's estimated to return between 3,100 and 3,400 kWh per year.
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To be honest last time I looked prices were way out but this is like 5-7 years ago.
As a family Avro estimated a usage of around 9400kwh, I'm now monitoring everything in order to get a good picture for the consideration of solar / battery.
I'd maybe have around £10k to play with as we are also remortgaging to get us out the help to buy, anymore than £10k on top will push us over the 75% LTV which I'm wanting to try and stay under.
I've not done much research into solar/battery to be honest and it has only since owning an EV I've started to consider the move to Solar.
I'd love to rely less on the grid, take advantage of the overnight cheaper electric and also have the warm fuzzy feeling of helping the environment.
very close to me, who did your install?
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RB Grant. Had it all done in a little over half a day. Guys were doing the panels while the electrician was running cables, fitting inverter etc. The panels were fitted by back of 1 with the electrician finished about 2:30.
Our house when we bought it came with a 20 panel/3.9KW peak system which is still under an old Feed in Tariff. I'm keen to get a battery but not sure how difficult/expensive/practical that is. Will keep an eye on this thread. Need to look into it actually, we're still getting FiT payments but our electricity bills have rocketed recently.
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The thing about battery without solar, is you still need most of the management/regulation/switching kit, which is a definite part of the cost. The benefit of battery+solar is that it's not much more work than just solar, IMO.
Plus it makes sense to add a battery so any solar you produce "for free" can be stored and used. Odds are, the money you get feeding the grid is not as much as the money you'd save using battery over mains. Cost of batteries obviously impacts this.
Plus it makes sense to add a battery so any solar you produce "for free" can be stored and used. Odds are, the money you get feeding the grid is not as much as the money you'd save using battery over mains. Cost of batteries obviously impacts this.
You definitely only want to be selling it to the grid as a last resort unless you are on one of the old FIT deals the payback is tiny for selling it but at least they have finally sorted it so you get something! To maximise solar you want an EV, a battery bank and an immersion heater!
I generally export all my energy from the battery at peak times, as I am on Agile Export with Octopus, the last 7kWh I sent this evening was paid at 32p (avg) per unit, but it only costs me 15.46p per unit to import at the same time of day using the import tariff, and I don't use anywhere near 7kWh. I charge the battery at 20:30 onwards at 5.5ppkWh, and then discharge it again in the AM peak, which is about 18p per unit, and then it trickle charge throughout the day from the solar. So today I made ~£3.12, and over the past week I have made quite a bit more than that, if every day were like today, the battery would pay for itself in less than 2 years!
